Some sites like Escortsanbabes or Scarlett Blue actually take glamour photos for the girls as a condition to advertise on their sites, so the initial photos are real.
But after that, all that a girl has to do is to pay for the advertising money to get access to post. Even if they left, they still can let their friends use the access and photos to advertise.
So, the photos are real, but they might not belong to the same girl ! And also, the photos are heavily photoshopped.